Firefighters are battling the Sand Fire in Yolo County, the first major blaze of the season, which has burned hillsides thick with brush. The blaze broke out Saturday afternoon and firefighters continued to fight flames overnight.

Powers says the number-one factor impacting efforts today will be the hot weather.

"We're most concerned about the heat, the really high temperatures and the low relative humidity in the area," he says. "There's supposed to be a little bit of wind but the biggest concern is the high temperatures.

The fire broke out amid a heat wave gripping Northern California; the hot weather with temperatures in the 100s is expected to continue Monday.